Her comments about casual gamers are spot on. Hell, I have almost 2000 hours in the game (since Alpha 6) and the AI changes to destroy mode are @%$#ing me off to the point I don't want want to do BM hordes any more and I'm not the only one on our server that feels this way. I just listened to my husband giving a hour long (and still going) rant on the subject and he has been playing since pre-Alpha.
It seems that on solo games they are coming out of destroy mode but when they enter destroy area mode on dedicated servers, they never come out of it. Even of Liz's SP test game, she has an example where they had two paths to her and none of the zeds would even try to get to her. 50% destroy area seems a bit ridiculously much and with them never coming out of destroy mode, all of them will being in destroy mode in very swift order. That's not any fun to play. I watched 1 BM zed spawn within eyesight 1 block above the ground, fall and ragdoll then permanently enter destroy mode with no damage to the zed taken.